The present invention relates to a digital interface device for PCM data, in particular for digital telephone, data processing or image processing systems.
As is known, in the telephonic field, analog exchanges and systems are being gradually replaced with exchanges and systems of the digital type which, besides allowing a better processing and transmission of phonic signals, also allow the execution of data processing functions and the integration of different tasks in a same system, in particular for example for the obtainment of an increasingly complete office automation and a rational use of available resources.
Furthermore, it is well known that said digital systems use, for the transmission of both phonic and informatic data, a PCM time sharing coding, which allows simultaneous transmission on a single line of a plurality of signals, possibly conveniently sampled and sent, as successive sequences of groups of binary signals, in defined time intervals (time slots) on said channel, each signal being associated with a specific time slot in each transmission period.
Said digital systems often require the presence of a processing unit which controls the terminals and the various units constituting said system on the basis of one or more application packages and which can dialog with said controlled units by means of a PCM bus comprising one or more PCM channels. Thus, in view of the different signal control characteristics of existing processing units and of the PCM channels, an appropriate interface is necessary in said systems for allowing the dialog between the central processing unit and the terminals or units controlled thereby.